Greg wrote:DewiSant wrote:If a weight has hit it on the face and has actually dented through to the back all you need is it being laid on a polished steel surface and put under a hydraulic press - if one used a (for arguments sake) fifty ton press with a 3" diameter ram and on the inside of the platter place a smaller, say 1/2" diameter piece of steel right on top of the dent then the tonnage you can apply in that one place is phenomenal
Sounds good. Where do you suggest we and in particular Thomas access' that very useful service?
Actually, I don't think you are getting what is required here, but I'm happy to eat my words if you can explain adequately. Please have a go!
eyes down look in for a full house
I will do my best for you
1) when your car has a 'dint' in the wing a good bodywork man can 'tap' the back of the dint until it reforms into its original shape without the use of handfuls of filler compound i.e. a Rolls Royce bodywork man or any really competent bodywork man for that matter
2) unless the platter had something seriously heavy dropped on it the same applies in that 250/300 tons applied to the back of the platter over the dint would be enough to force the dint back into position whether it wants to go or not it has little choice in the matter -
3) thus as no material has been removed from the platter if it was balanced before it was struck by an unknown object it should be after
4) because the spring in the metal may allow it to spring back a thou or two when the ram pressure is released from the platter when this is measured using a Dial Test Indicator if it has dropped back say for arguments sake three thou then placing either a three, four, five or six thou brass shim under the platter or even Aluminium plate then repressing the platter should take it past it's normal position then when the pressure is released it will spring back exactly where it should be
5) using a Dial Test Indicator with 0.0001" (a tenth of a thousand of an inch) resolution it would be possible to get her back as near perfect as possible
6) another possibility would be to keep the ram pressure on the back of the platter for perhaps a week then there is less likelihood of it springing back at all because the metal will give even more under sustained pressure rather than a quick burst of it then letting the pressure off
7) now for the platter slipping on it's tapered spindle - these tapers cannot fail to grip unless something is restricting it - if the spindle has a seat/landing/step directly under where the taper ends on the spindle guaranteed that's why it is seating properly and needs locktite to help it grip
this can be easily proved quickly with some 'engineers blue' - with a cotton bud apply a thin film to the tapered bore of the platter and the underneath of the platter bore - clean the platter tapered spindle as clean as you can possibly get it (use some metal polish like brasso) then clean it with petrol or other solvent until it is spotlessly clean - drop the platter onto the spindle and rotate it back and forth - lift the platter back of and you will find 'witnesses' of where it is touching and where it is not - a heavy transfer of 'blue' is where there is a problem -
9) if the only heavy blue witness is on the tapered part of the spindle then it is the finish of the platter bore or spindle taper that is stopping it seating properly - you should be able to see where they are not touching quite easily with the 'lack' of blue in any position -
10) if the tapered bore of the platter is at fault then it just needs polishing until it seats properly - TAKE GREAT CARE NOT TO REMOVE ANT REAL MEAT FROM THE BORE - we are on about tens of thous here not even one or two thou because the amount one or two thou removed will make to where it seats back onto its spindle is not the one or two thou you have removed but probably twenty or thirty thou at LEAST
11) if the 'rough' is on the spindle then it must be removed from the unit and polished until it seats properly - again you
must not overdo it because the same as polishing the bore to much applies
hope this explains it more for you
Dewi
Yeah! Tell 'em Bro!
